Weeds cause tremendous global economic losses by reducing crop yields and lowering crop quality. In the United States alone, agronomic crops must compete with hundreds of weed species. Moreover, some crop damage due to inadvertent overexposure to certain herbicides used to control undesirable plant species has occurred.
Accordingly, there is ongoing research to discover and develop more effective herbicidal agents for the selective control of weeds in the presence of crops. If successful, inadvertent overexposure to such agents will cause less crop damage, and perhaps eliminate such damage altogether.
Certain benzodiazepine compounds are known to possess antianxiety, antibiotic, blood pressure-lowering, respiratory-depressing, antiataxia and/or anticonvulsant activity (see, e.g., U.S. Pat. Nos. 3,681,341, 3,947,408, 3,985,732, 4,031,079, 4,185,016, 4,316,839, 4,352,815, 4,352,817 and 4,772,599; W. B. Wright, Jr., et al, Journal of Medicinal Chemistry, 21, pp. 1087-1089 (1978); P. J. McCloskey and A. G. Schultz, Journal of Organic Chemistry, 53, pp. 1380-1383 (1988); T. T. Tita and M. J. Kornet, Journal of Heterocyclic Chemistry, 24, pp. 409-413 (1987); M. Mori, et al, Tetrahedron, 42, pp. 3793-3806 (1986); T. Nagasaka, et al, Tetrahedron Letters, 30, pp. 1871-1872 (1989); A. G. Schultz, et al, Journal of the American Chemical Society, 109, pp. 6493-6502 (1987); E. Wolf and H. Kohl, Liebigs Ann. Chem., pp. 1245-1251 (1975); A. Kamal, Journal of Organic Chemistry, 56, pp. 2237-2240 (1991); R. Singh, et al, Indian Journal of Chemistry, 20B, pp. 129-131 (1981); and A. E. Azzouny, et al, Pharmazie, 32, pp. 318-323 (1977)).
However, no herbicidal utility for the benzodiazepine compounds is disclosed or suggested in those patents and publications.
It is an object of the present invention to provide a method for controlling undesirable plant species with benzodiazepine compounds.
It is also an object of the present invention to provide a method for the selective control of undesirable plant species growing in the presence of cereal crops using those compounds.
It is yet another object of the present invention to provide herbicidal compositions containing those benzodiazepine compouns. These and other objects of the present invention will become more apparent from the detailed description thereof set forth below.